Changes /admin/application_settings to support template repository selection in EE

app/assets/javascripts/pages/admin/application_settings/index.js

 import initSettingsPanels from '~/settings_panels';
+import projectSelect from '~/project_select';
 
 document.addEventListener('DOMContentLoaded', () => {
   // Initialize expandable settings panels
   initSettingsPanels();
+  projectSelect();
 });

app/views/admin/application_settings/show.html.haml

@@ -325,6 +325,8 @@
   .settings-content
     = render partial: 'repository_mirrors_form'
 
+= render_if_exists 'admin/application_settings/templates', expanded: expanded
+
 %section.settings.as-third-party-offers.no-animate#js-third-party-offers-settings{ class: ('expanded' if expanded) }
   .settings-header
     %h4